When viewing a volume rendering of a 3-dimensional medical dataset it is frequently necessary for a user to crop the 3-dimensional medical dataset in order to more clearly view the desired anatomical structure. Cropping removes a portion of the 3-dimensional medical dataset in order to more clearly illustrate underlying structure. According to conventional techniques, a user must first select a crop plane to be adjusted and then control the positioning of the crop plane in order to crop only the unwanted portion of the image. A user would typically use a user interface device, such as a mouse or trackball, to first select the crop plane and then reposition the crop plane by dragging it with the user interface device. While effective, this conventional technique of cropping a 3-dimensional medical dataset is far from ideal, particularly in a sterile environment needed for surgery or other invasive medical procedures.
For example, if a surgeon is using the 3-dimensional medical dataset for reference during a surgical procedure, the user interface device must be kept sterile. The very nature of a user interface device like a mouse of trackball makes it difficult to keep sterile. For example, a mouse typically has multiple buttons and a trackball needs to spin freely within a keyboard or other mounting fixture. If covered in a sterile cover, the functionality of both devices may be somewhat compromised. It will also be necessary for staff to perform extra steps before each surgical procedure to ensure the sterility of the user interface device. Additionally, it is oftentimes awkward and inconvenient for the surgeon to transition from a workstation with the user interface device to the patient while performing a procedure.
Therefore, for these and other reasons, an improved method and control system for manipulating a 3-dimensional medical dataset is desired.